FXUS61 KILN 272331 AFDILN AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE WILMINGTON OH 631 PM EST FRI NOV 27 2009 .SYNOPSIS... HIGH PRESSURE WILL BUILD INTO THE REGION TONIGHT AND WILL CONTROL THE REGIONS WEATHER INTO EARLY SUNDAY. A COLD FRONT WILL MOVE INTO THE OHIO VALLEY BRINGING THE NIGHT CHANCE OF RAIN ON SUNDAY AND SUNDAY NIGHT. && .NEAR TERM /UNTIL 6 AM SATURDAY MORNING/... HIGHLY AMPLIFIED UPPER LEVEL FLOW PATTERN WITH LOW PRESSURE OVER THE EASTERN GREAT LAKES SHIFTING EAST AS LARGE RIDGE BEGINS TO BUILD EAST FROM THE NATIONS MID SECTION. SFC RIDGE TO BEGIN BUILDING IN THIS EVENING. WITH LOW LEVEL FLOW TRANSITIONING FROM CYCLONIC TO ANTI-CYCLONIC EXPECT CLDS TO CLEAR FROM THE SOUTHWEST. WITH CLEARING SKIES AND LIGHT WINDS HAVE TRENDED OVERNIGHT LOWS ON THE COOL SIDE OF GUIDANCE ENVELOPE. && .SHORT TERM /6 AM SATURDAY MORNING THROUGH MONDAY NIGHT/... IN AMPLIFIED SPLIT LEVEL FLOW PATTERN UPPER LEVEL RIDGING WL BUILD OVER THE REGION ON SATURDAY. EXPECT TO SEE A GOOD AMOUNT OF SUNSHINE WITH MODERATING TEMPERATURES. HAVE TRENDED SATURDAYS HIGHS CLOSER TO COOLER MAV NUMBERS. THE FLOW BACKS WITH AN INCREASE IN CLOUDS LATE SATURDAY NIGHT INTO SUNDAY. HAVE TRENDED SAT NIGHTS LOWS A LTL COOLER THAN GUID BASED ON EXPECTED SLOWER ONSET OF CLDS. WEAK ISENTROPIC LIFT DEVELOPS AHEAD OF AN APPROACHING COLD FRONT ON SUNDAY. NUMERICAL MODEL SOLN/S A LTL SLOWER AND THEREFORE HAVE SPREAD CHC POPS FOR SHOWERS INTO THE NW SUNDAY AFTN AND THEN INCREASE POPS TO LIKELY OVERNIGHT SUNDAY. HAVE ENDED POPS FROM THE NW MONDAY IN THE WAKE OF THE FRONT. SFC HIGH PRESSURE TO RESULT IN DRY WEATHER MONDAY NIGHT. HAVE TRENDED SUNDAYS HIGHS A LTL BELOW GUID DUE TO CLDS AND PRECIP AND SLIGHT ABOVE SUNDAY NIGHT. && .LONG TERM /TUESDAY THROUGH FRIDAY/... IN SPLIT UPPER LEVEL FLOW PATTERN CONFLUENCE OVER THE REGION RESULTING IN SFC RIDGING. THIS WILL PROVIDE GENERALLY DRY WEATHER TUESDAY INTO EARLY WEDNESDAY. SRN STREAM SYSTEM TO EJECT FROM THE GULF STATES NE INTO THE OHIO VLY AND MERGE WITH THE NORTHERN STREAM AS A BROAD TROF DEVELOPS ACROSS THE GREAT LAKES. LATEST GFS SOLN KEEPS THIS SYSTEM FAR TO OUR EAST WHILE THE MORE CONSISTENT ECMWF AND ENSEMBLES BRING IT INTO THE OHIO VALLEY. WL FOLLOW THESE SOLN/S SPREADING CHC POPS FOR RAIN SHOWERS FROM THE SOUTH WEDNESDAY AFTN. WL CONT CHC POPS INTO THURSDAY MORNING WHEN A COLD FRONT IS EXPECTED TO PASS THRU. WITH BROAD TROF UPR LEVEL ACRS THE GREAT LAKES...SFC HIGH PRESSURE EXPECTED TO NOSE INTO THE TN VLY LATER THURSDAY INTO FRIDAY. HAVE MAINTAINED A DRY FCST THRU THE END OF THE WEEK WITH TEMPS BELOW NORMAL. && .AVIATION /00Z FRIDAY THROUGH WEDNESDAY/... AFTER 3000 FT CEILINGS LEAVE DAY...CONDITIONS WILL BE VFR THROUGH THE FORECAST. SKIES WILL BECOME MAINLY CLEAR AT ALL SITES BY 06Z. WINDS WILL SHIFT TO SOUTH AROUND 12Z...WITH SPEEDS UP TO 10 KNOTS. OUTLOOK...MVFR CIGS AND VSBYS POSSIBLE SUNDAY NIGHT/MONDAY. && .ILN WATCHES/WARNINGS/ADVISORIES... OH...NONE. KY...NONE. IN...NONE. && $$ SYNOPSIS...AR NEAR TERM...AR SHORT TERM...AR LONG TERM...AR AVIATION...CONIGLIO